In Colorado, an ad from Republican Senate candidate Jane Norton calls on Obama to "pledge to balance the budget or else decline to seek reelection. That would be change we can believe in."
In Nevada, Republican officials have set up a conference call with Minnesota Gov. Tim Pawlenty to push back on the president's visit.
The latest ABC News/Washington Post poll found that Republicans have been able to capitalize on doubts about the president's job performance to grow more competitive in challenging Democrats in November.
A party official said Obama will be critical for Democratic candidates by helping to jump start "organizing at the local level and building a robust grass-roots fundraising effort."
The president will be looking for opportunities to help candidates who "share his vision for advancing an agenda through Congress that makes progress on issues that have been ignored in Washington for too long," an administration official said, citing health care reform, regulatory reform and a jobs bill.
Administration and Democratic Party officials would not say where Obama will campaign over the next few months or which candidates have requested his time.
But already, one Democratic candidate has raised the possibility that Obama may not be a welcome addition at a campaign rally.
Richard Blumenthal, Connecticut's attorney general who is running for retiring Sen. Chris Dodd's seat, said on Monday that it was "an open question" whether he would ask Obama to campaign on his behalf.
When asked if the president lending a hand would help or hurt his campaign, Blumenthal deferred: 'I can't comment."
Asked about Blumenthal's comments, an Obama administration official said they "wouldn't describe that as something anyone here obsesses over."
Matt Dowd, an ABC News contributor who served as chief strategist to Bush-Cheney 2004, said Obama should just stay put in Washington and skip the trail for now.
"The best thing Barack Obama can do right now is not go out and campaign for somebody but go and fix the situation or attempt to fix the situation in Washington in a real way," Dowd said. "That actually can provide a better halo effect than him showing up with a 49 percent job approval rating."
Democratic Party officials and administration officials didn't dispute that premise and agreed that having legislative accomplishments to point to could bring a boost on the campaign trail for their candidates.
"When the president's agenda advances through the Congress, it benefits both the members of Congress and the president, and it enhances the standing of both members of Congress and the president," an administration official said. "Good policy is good politics. Demonstrating the ability to get things done in Washington is going to be an important part of enhancing the president and Democrats in Washington's political standing."
That may be easier said than done given the partisan gridlock on Capitol Hill and the difficulty of pushing through any contentious legislation in an election year.
Dowd believes that Obama hitting the trail for Democratic candidates at this stage in the election cycle is "high risk, very little reward" for both the president and those whose names are on the ballot.